Bees, in this case, aren't actually yelling or whispering using voices, but via chemical communication -- by releasing pheromones that signal different kinds of messages.
The bee whisper comes into play when a colony member finds a new source of nectar. That bee doesn't want to give away the location to just any old honey bee; it wants only its friends and family back at the hive to find out. So it releases a delicate pheromone, which quietly signals the new food source without calling too much attention to itself.
Other bees -- specifically several species in Brazil -- aren't so tactful. These bees prefer to shout. In this case, a much louder pheromone is released -- one calling brazenly to the rest the hive, ostensibly as a signal to would-be intruders that a bunch of allied bees are on the way, so don't even think about copping a bite.
"It's a signal with honest aspects and the possibility of lies," said James Nieh, a professor of biology at the University of California San Diego who oversaw the Brazilian bee research. "It tells nestmates where to find good food and hints at a larger occupying force."
The research was mostly carried out by postdoctoral researcher Elinor Lichtenberg. She recently published her bee study in the journal Cell Biology.
She says the new study is evidence that eavesdropping can inspire other bees to not only adopt whispers but also new techniques like shouting.
"Our study provides a new way of looking at how eavesdroppers affect the evolution of animal communication signals," she said. "Until now, it was thought that eavesdroppers select against conspicuous signals, for example by more easily finding and eating prey that sings loudly. But our results show that eavesdroppers can help select for the same conspicuous signals that are easiest for intended recipients to detect and understand."
The intense competition for food between colonies, she says, continues to push bee species to evolve their communication techniques.